Execption in AOP Logging Program Issue

[sumanta panda]

Dear All,

I am new to spring and using spring 2.0. I am writing an AOP Logging program.

I am not getting compilation error.
While running the Main.java I am getting warning log4j:WARN No appenders could be found for logger (org.springframework.context.support.ClassPathXmlApplicationContext).
log4j:WARN Please initialize the log4j system properly.

My doubt is what i will add the syntax of code in Main.java so that i am getting the output.

[b]”I have added the jar files in the class path .asm-2.2.3.jar, asm-commons-2.2.3.jar, asm-util-2.2.3.jar, aspectjrt.jar, aspectjweaver.jar, spring-aop.jar, spring.jar,log4j.jar, cglib-nodep-2.1_3.jar”

Below given is my code.

Greeter.java

package com.earldouglas.greeter;

public interface Greeter {
    public String getGreeting();
}

DefaultGreeter.java

package com.earldouglas.greeter;

public class DefaultGreeter implements Greeter {
    public String getGreeting() {
        return "AOP Logging";
    }
}

MethodLogger.java

package com.earldouglas.aoplogging;
import org.apache.log4j.Logger;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;
import org.springframework.util.StopWatch;
@Component
@Aspect
public class MethodLogger {
    @Around("execution(* com.earldouglas..*.*(..))")
    public Object timeMethod(ProceedingJoinPoint joinPoint) throws Throwable {
        StopWatch stopWatch = new StopWatch();
        stopWatch.start();
        Object retVal = joinPoint.proceed();
        stopWatch.stop();
        StringBuffer logMessageStringBuffer = new StringBuffer();
        logMessageStringBuffer.append(joinPoint.getTarget().getClass().getName());
        logMessageStringBuffer.append(".");
        logMessageStringBuffer.append(joinPoint.getSignature().getName());
        logMessageStringBuffer.append("(");
        logMessageStringBuffer.append(joinPoint.getArgs());
        logMessageStringBuffer.append(")");
        logMessageStringBuffer.append(" execution time: ");
        logMessageStringBuffer.append(stopWatch.getTotalTimeMillis());
        logMessageStringBuffer.append(" ms");
        Logger.getLogger(this.getClass()).info(logMessageStringBuffer.toString());
        return retVal;
    }
}

Main.Java

package com.earldouglas.aoplogging; 

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.FileSystemXmlApplicationContext;
import org.apache.log4j.*;
import com.earldouglas.greeter.DefaultGreeter;

public class Main{
	public static void main(String[] args) throws Exception { 

		ApplicationContext ctx= new FileSystemXmlApplicationContext("MethodLoggerTest-context.xml");
		
		}
		}

MethodLoggerTest-context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd"> 
      <aop:aspectj-autoproxy />
    
    <context:component-scan base-package="com.earldouglas.aoplogging" />
    <bean class="com.earldouglas.greeter.DefaultGreeter" />
</beans>

Please help/advise me on resolve this issue. .

Thanks for your time.

Best Regards,
Sumanta Panda

[Hong Anderson]

You have to provide log4j configuration. Consult log4j documentation.

[sumanta panda]

Dear All,
My doubt is what is the piece of code i will add in the Main.Java so that i am able to getting the output.

Please suggest.

Thanks for your time.
Regards,
Sumanta Panda

[anshu mishra]

In MethodLoggerTest-context.xml file, add an "id" to the bean

<bean id="defaultGreeter" class="com.earldouglas.greeter.DefaultGreeter" />

In your java code append these two lines :-

   DefaultGreeter defaultGreeter = (DefaultGreeter) ctx.getBean("hello");
   defaultGreeter.getGreeting();
  

[Vivek K Singh]

there are two issues here:

First: The warning you are getting is generated by log4j, You need to configure log4j to remove this warning. To do that create a log4j.xml configuration file and add a category like this. Also have commons-logging.jar on the class path.

<category name="org.springframework">
      <priority value=<<your log level like "info","debug" etc >> />
</category>

Second: In Main you are just instantiating the spring context, you are not calling anything. So follow the suggsation by Anshu and call the greeter method.

Just a tiny change:

   DefaultGreeter defaultGreeter = (DefaultGreeter) ctx.getBean("defaultGreeter");   
   defaultGreeter.getGreeting();